The present invention relates to an exposure unit for the manufacture of a semiconductor device, a semiconductor production system formed by combining a plurality of such exposure units in a communication network, and a method for manufacturing a semiconductor based on such a system.
In a standalone type semiconductor exposure unit (stepper) not network-connected by an LAN or the like, in general, it is necessary to provide a data file group such as a required job file or reticle file individually for each stepper. This has caused for an operator a troublesome operation of loading necessary data in a local storage included in a desired stepper arranged in a clean room with the use of a removable storage medium such as a floppy disk (FD) or a photomagnetic disk (MO), for example, storing a necessary data file.
There are conventionally many semiconductor manufacturing plants managed in compliance with a protocol of the Semiconductor Communication Standard (SECS), commonly known as an online system, on the other hand, connected to a host computer by a low-speed serial line such as RS232C. In such an online system, it is possible to perform control of the stepper using a command, status control of the stepper, and partial modification of date files.
In an online system, as described above, a data file such as a job file or a reticle file used for an exposure operation can be switched over by an online command. For a data file itself having a relatively large data capacity, however, the online system employs a low-speed line in many cases, and as a result, a configuration permitting transmission on the line is not used. It is, therefore, necessary to previously provide these files on steppers conducting exposure.
In a general semiconductor production system, therefore, the only function of the host computer is to determine a kind of exposure operation in each of the steppers connected in a communication network, and to request a start of the exposure operation. As a result, a data file containing exposure work information (known also as a job) showing contents of the work to be executed must be present on the stepper to be used for exposing the semiconductor. Consequently, when using a plurality of steppers, all the steppers are required to have all pieces of exposure work information which may be necessary in the individual storage areas.
The configuration as described above is, however, defective in that it is necessary to previously investigate and collect all pieces of exposure work information which may be necessary, causing complicated maintenance and management of exposure work information.
Further, it is probable that the stepper has in the storage area thereof pieces of exposure work information that will never be used. It is, therefore, necessary to increase the capacity of the storage area, thus resulting in economic demerits.
Particularly, hundreds or even thousands of files are required for productions of some sorts of semiconductor devices, and providing all these files on the stepper is heavy on the storage capacity of the stepper and finally leads to a shortage of the capacity. In addition, in the exposure process using a number of data files such as ASIC, there is a demand for smooth and efficient management of these files. Preparing and compiling operations of these data files are conducted outside of a clean room, and in many cases, correction of defects in parameters and modification of trial parameters are performed very often. This leads to a demand for automatic updating of files via a network into the latest ones as requested.